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    <meta charset="UTF-8">
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    <title>Document</title>
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<body>
    <script>
        //1.判断当前对象是否为某个实例
        let d = new Date();
        let arr = new Array();
        console.log(arr instanceof Array);
        console.log(d instanceof Date);
        console.log(arr instanceof Date);


        // 2,判断是否为数组
        console.log(Array.isArray(arr));
        console.log(Array.isArray(d));
    </script>
</body>
</html>